Radiator pressure cap



Sept. 5, 1950 B. E. CLARK ET AL 1,201

RADIATOR PRESSURE CAP Filed Feb. 23, 1949 INVENTORS. GERALD K. VIESON BYBRUCE E. CLARK QTTORNEV Patented Sept. 5, 1950 RAmA'roR PRESSURE CAPBruce E. Clark and Gerald K. Vieson, ,Dearborn, Mich.

Application February 23, 1949, Serial No. 77,708

6 Claims. (01. 220-44) The present invention relates to a radiatorpressure cap which is adapted to relieve both excessive pressures andnegative pressures created within an engine cooling system utilizing acoolant liquid and a radiator.

Radiator pressure caps which have been developed previously to controlpressure conditions in such a cooling system and to relieve conditionsof excessive pressure and negative pressure have utilized two separatespring loaded valves. Such a construction is expensive and is notpositive due to variations in the spring characteristics.

Therefore, a principal object of the present invention is to provide aradiator pressure cap which controls pressure within the radiator andwhich is simple in construction and contains a relatively small numberof parts.

A further object of the present invention is to provide a radiatorpressure cap which contains only one valve assembly to accomplish apressure normalizing effect when either excessive or negative pressuresexist in the cooling system.

Other objects of this invention will appear in the following descriptionand appended claims, reference being had to the accompanying draw ingsforming a part of this specification wherein like reference charactersdesignate corersponding parts in the several views.

In the drawings:

Fig. 1, is an elevation in section showing a radiator cap embodying thepresent invention attached to the filler spout of a radiator.

Fig. 2 is an elevation in section of the radiator cap of the presentinvention.

Fig. 3 is an elevation, partly in section, showing the position of theparts of the radiator pressure cap of the present invention when thereis a negative pressure or partial vacuum in the cooling system.

Fig. 4 is an elevation, partly in section, showing the position of theparts of the radiator pressure cap of the present invention when thereis an excessive pressure in the cooling system.

Before explaining the present invention in detail it is to be understoodthat the invention is not limited in its application to the details ofconstruction and arrangement of parts illustrated in the accompanyingdrawings, since the invention is capable of other embodiments and ofbeing practiced or carried out in various ways. Also it is to beunderstood that the phaseology or terminology employed herein is for thepurpose of description and not of limitation.

In the drawings, the top chamber or header of a radiator is indicated bythe numeral It. A 66 2 neck [I extends upward from the said header andconnects with the flller spout I2. An annular bead l3 surrounds theopening in the top of the neck II, and an overflow pipe or vent l4 leadsfrom the filler spout IE to the open air. The upper edge of the fillerspout i2 is rolled over to provide the collar IS in which are formedelements of the conventional bayonet lock (not shown) for detachablyholding the radiator pres- .sure cap in position.

The radiator pressure cap of the present invention consists of a cap l6which is formed with a circular groove l1 and a centrally located springseat l8. The cap I6 is also formed with a downwardly and inwardlyextending flange l9 which is adapted to engage the overturned end of thecollar 15 in a'conventional locking engagement such as the bayonet typeengagement whichis well known in this art.

An upper cup member 2a is located in place over the guide member 2|formed by the annular groove I in the cap It. The top part of the uppercup member 20 is formed into a downwardly extending resilient retainermember 22. This retainer member acts as a sealing gasket when in theposition shown in Fig. 1. The lower part of the upper cup member 2% isinturned to form the surface 23.

Extending through the bottom opening of the upper cup member 26 is thelower cup member 24. The lower cup member 2a is closed at its bottom,and flared at its top to provide the surface 25. A shoulder portion 26is formed near the top of the lower cup member 24, and a plurality ofholes or ports 2'! are spaced around the circumference of the said lowercup member 2 1 near its bottom. A resilient stopper 28 is fitted aroundthe lower portion of the lower cup member 24 and extends against theshoulder 26. A coil spring 29 is disposed between the spring seat I8 inthe cap l6 and the bottom of the lower cup member 24.

Attachment The radiator pressure cap shown in Fig. 2 is attached to aradiator in the position shown in Fig. 1 as follows:

The stopper 28 is inserted in the flller spout l2 and over the topopening of the neck H. The stopper 28 seats against the bead l3. Forceis exerted downwardly on the cap It, the coil spring 23 is compressed,and the surfaces 23 and 25 separate to form the opening or gate At thesame time, the end of the resilient retainer member 22 contacts thecollar [5 on the filler spout 3 I2, thus closing and sealing the cap l6under tension. In this position a sealed cooling system is provided sothat none of the coolant escapes.

EIECCSSi C 2378881116 condition Fig. 4 demonstrates the position of theelements of the radiator cap of the present invention when there isexcessive pressure in the cooling system of a vehicle. Thiscondition mayresult in several ways. If the radiator is filled while the motor iscool, there is a natural expansion of the fluid when it is heated andwhen circulation begins. Another way in whiclrthe' condition results iswhen the cooling system overheats and the coolant is converted tosteafir or vapor.

When the pressure in thecooling; systenr ex ceeds a predetermined amount(determined by the pressure characteristics of the spring 299 thestopper 2 8 is forced upward against the tension-of the spring zs whencompressed and is lifted clear of the bead I3 providedin' the neck ll.With the stopper 28: thus raised, the excess pressure and vapor orcoolant is" allowed to escape along the' path indicatedby the arrows,-Fig. 4', through the neck I I, past the stopper 28, and out the vent'oroverflow pipe l4. When thep're'ssure in the cooling system is reducedbelow the predetermined amount required to lift the'stopp'er 28 againstthe tension of the spring 2 9', the

stopper. 28"returns under tension ofthe' spring 2s mthe closed position;

Negative pressure condition when the coolant as; nce; been heated'an'dmen the coolant and cooling system isallowedto cool, a partial vacuum ornegative pressure is' created in the cooling system which, if riot re:leased, might bring about a collapse of the radiator header. Whenthiscondition prevails, the elem'er'its of the radiator: pressure cap;of the present invention are in the positionshown in Fig. 3.'

The unequalpressures inside saute sidethe cooling system causethe'lip'j3'l of the stopper 18" to be forced away from the lower'cup i4,as'ind'i cated in Fig. 3-. This" a'ctioriuncovers the holes or ports21, and the outside air follows the path indicated by the arrows; througthe-vent or overflow 'pipe [4,- the' dpeningor "ate some ports 21,: andthe neck H' int-o thec'oo g system. When the pressure withinthe eooim gsy tem returns to normal, the lip- 3! 6fthe stopper "2'8 returns.- tothe notifier positiorr and covers th" p 3 The hardness of the rather orother" resirw material of which the stopper is made-armtl'i' thicknessof the sectionof seen in tri'al were: lied uporrto regulate thfire'ssndiffer' nai which the 11p will be forced awajfrom 'th vacuum renerports"?! to afliriifi an fi'difi tfi l4 and filler spout l2 to satisfythe vacuum within the cooling system ataalpoint below which the radiatorheader in will collapse. Depending uponthe structure of the radiatorii-eases" Hi, this is'generally found to' be in the neiglib'o'rliood often pounds 7 v Referring to Fig. 2, it will be newsman-1e surfaces 23and 25 are in contact under tension of the spring 29 when the radiatorpressurecan is removed from the filler sp'outl2 of a radiator; Thisconstru'ctior'rprevents dirt and foreign mat ter'from accumulating inthe interior'construc tionof the device:

The spring 29 is a low rate spring.-

That is,

it is a spring which has a low rate of change in tension as it iscompressed. The device of the present invention is designed to permituse of a relatively long spring which aids in establishing such a lowrate. This enables the spring to exert as nearly as possible a constantforce throughout the movement of the plug or stopper 28, and enables thesaid stopper to reset promptly after the blow on pressure is relieved.The device of the present invention has been so designed that whenmanufactured to usual manufacturing tolerances, the cap will hold thepressure within limits of approximately one pound variation.

Thus, it will be seen that the present invention provides .a simple andefficient radiator pressure cap which will effectively and closelycontrol the pressuresin a cooling system within predeterni'i'ffdliriii'ts'. A' feature of importance in a cap of the: present inventionis the ease of installation and replacement of the resilient stopper 28.As will beseen, this stopper is held' in place; at the top by theshoulder 26, but is removable from; the cap by a pull in a downwarddirection. Thus if the. stopper becomes worn or loses its resiliency itmay readily be removed from the cap and re- 1. In a cooling system, afiller spout provided witha seating bead around thelower openingthereof,a neck communicating with the lower opening of said filler spout, aventor overflow pipe leading from said fillerspout, a closure memberremovably connected to' said filler spout and comprising a cap, means tolock-said cap to said filler spout, a hollow telescoping cup memberextending downwardly fromsaid cap and having circumferentially spacedholes near the bottom thereof, a spring interposed within said cupmember between said cap and the bottom of said cup member, 7 a resilientstopper surrounding the lower portion of the said cup member andnormally covering the holes therein and movabl-y seating onsaicl seatingbead. I 1 I 2. A device as claimed in claim 1- and further characterizedin that a shoulder portion isformed on the said cupmember to prevent thestopper from moving upwardly out ofplace.

3. In a radiator pressure cape of the type wherein pressures-within aradiator are controlled by valvemeans-disposed-withirra hollow cupmember communicating with the open air and extend ing into" the fillerspout of a radiator, a combined excessive pressure and vacuum reliefvalve com prising a hollow telescoping cup member extending downwardlyfrom a closure-member and having spaced holes in the lower portionthereof, a-

spring inter-posedbetwe'n the said closure mem ber and the bottom ofsaid cup member, and aresilient stopper movably seated on the opening atthe bottom ofthe, filler spout, stopperbeing disposedaround-saidcupmemberand having a lower portion relatively thin incrosssectioncoverin'g. the said holes in the normal. position whereby saidportion will move" to open the saidhol'es' when the pressure of theatmosphere ex ceeds by a predetermined amount the pressure within theradiator.

4. A device as claimed in claim 3 and further characterized in' thatashoulder portion is formed" in the side wallof the said cup member abovesaid spaced holes to prevent the stopper from moving upwardly out ofplace.

51 A: device as olaimedin-claim Z aI-id further characterized in thatthe said resilient stopper formed in the shape of an inverted truncatedcone which extends into the opening in the bottom of the said fillerspout in the seated position.

6. A radiator pressure cap of the class described comprising a closuremember, an upper and a lower cup member in telescoping engagement andextending downwardly from said closure member, said lower cup memberhaving circumferential holes near the bottom thereof and a shoulderformed above said holes, a spring disposed within said cup member, aresilient stopper disposed around the lower cup member and against theshoulder provided therein and normally covering the said holes in thelower cup member, and surfaces formed near the bottom of the upper cupmember and the top of the lower cup member which provide a gate andwhich closes when the cap is free from a, radiator and which opens whenthe cap is in its attached position.

BRUCE E. CLARK. GERALD K. VIESON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,006,752 Swank July 2, 19352,124,648 Brennan July 26, 1938 2,133,575 Rosenberg Oct. 18 19382,164,450 Eshbaugh et al. July 4, 1939 2,191,614 Frantz Feb. 27, 1940

